After 5mm of rain overnight, the going at Aintree on Thursday morning was described as Soft, Good to Soft in places on the National and hurdles tracks and Good to Soft, Soft in places on the Mildmay course.

What's the Grand National latest?

Last year's winner Many Clouds is the current 8-1 favourite as he attempts to become the first horse since Red Rum in the 1970s to win back-to-back runnings of the Aintree marathon.

Other leading hopefuls include Silviniaco Conti for Nicholls, with victory likely to thwart the Mullins attempt to emulate legendary trainer Vincent O'Brien by winning the British jumps championship.

Several leading National contenders require withdrawals before Thursday's deadline if they are to be guaranteed a place in the race, which has a maximum of 40 runners.

Lower-rated horses are balloted out and 2014 winner Pineau De Re - now a veteran aged 13 - is listed at 46 and needs six defections to make the cut.

Others in danger of missing out are Becher Chase winner Highland Lodge (47), Alvarado (48), who has twice finished fourth in the National, and Cheltenham Festival winner Cause Of Causes (49), who is rated about 20-1 to win the race.

Bishops Road, winner of the Grand National Trial at Haydock in February, is at number 41 for in-form rookie trainer Kerry Lee.

Annie Power beat My Tent Or Yours in the Champion Hurdle at Cheltenham

What are the Thursday highlights?

Annie Power faces Cheltenham runner-up My Tent Or Yours, trained by Nicky Henderson, as the first four home in the Champion Hurdle renew their rivalry.

Mullins also has Nichols Canyon, while The New One represents Nigel Twiston-Davies.

Leading steeplechasers will fight out the Betfred Bowl, with Mullins stablemates Djakadam and Don Poli - third at Cheltenham - taking on Cue Card, a late Gold Cup faller when in contention for the race eventually won by Don Cossack.

The Fox Hunters' Chase will see runners go over the National fences for the first time at the 2016 meeting.

Officials believe modifications to the fences introduced three years ago have helped improve safety.

Since the changes, there have been no fatal injuries in the National, although there were two equine fatalities in other races at the three-day meeting last year.

On The Fringe seeks a double double, having won the Cheltenham and Aintree Fox Hunters last year and followed up at Cheltenham in March.

Opposition includes Pacha Du Polder, runner-up in 2015 and fifth at Cheltenham under former cyclist Victoria Pendleton. Will Biddick rides this time for Nicholls.

Thursday's schedule

BBC coverage: Sarah Brett presents Afternoon Edition from Aintree on Radio 5 live from 13:00-16:10 BST, with the first five races live in the programme